The mind-boggling task of combining four casts for a three-night event aside, The CW will inevitably attempt to up the ante again this year, which could bring us a “true” four-way crossover. That’s what executive producer Andrew Kreisberg tells Entertainment Weekly, noting that the late addition of Supergirl to The CW’s lineup left it more difficult to coordinate their cast and crew schedules, whereas the early renewal of all four this year simplifies matters:

The thing that we didn’t really plan on — because we weren’t aware that we were going to switch Supergirl from CBS to CW and it was really going to be part of it — that was the one show that didn’t have built-in shut-down days, so all the other ones did. Melissa [Benoist] ended up being heavily in Flash and then in Arrow, so Supergirl was the one we needed to shut down the most and it was the one that we didn’t have any opportunity to. Now that we’ve gotten the early pickup and we’ve started designing the seasons, we’re building in those dark days, and actually more dark days on Supergirl than the other shows, to make it a little easier.

Topping last year’s crossover presents an interesting challenge, especially with the full addition of another cast to service. There’s also the likelihood of The CW picking up a fifth series in Black Lightning, though we’d likely need an army of nuclear physicists to figure out those logistics.

In the meantime, we’ve still the Supergirl and Flash musical (again taking place largely on the latter) to come, so stay tuned for additional details.